I'm an old medium-format film guy, too: Mamiya RB67 and Mamiya Universal with Gossen Luny Pro meter hanging around my neck. The newly announced Pentax 645Z looks so very interesting. I want to wait for a couple of things: 1) See Canon's next round of announcements, 2) Read the hands-on reviews and personal experience stories of 645Z early adopters. Normally, I tell people not to wait, because in the meantime you may be missing wonderful shots. In this case, however, I'm changing my stance. It has been so long since Canon launched a pro-level camera, I suspect there must be something coming soon; perhaps in August just ahead of Photokina. YMMV